There are common household technologies that are so advanced that, to me, they defy admiration. Sure, I can appreciate a pocket calculator and smart phone, but only in a superficial way, as if it was a magic trick. To really admire a piece of technology, you have to fully or nearly understand its workings.

For example, I stand in awe of the vernier scale as employed in measuring calipers. To me the concept of improving measurement twentyfold by simply sliding what amounts to two rulers relative to each other, is exceedingly cool. I appreciate the genius behind this because I almost, but not quite, understand why it works.

Maybe that's why I admire "magic" like cellphones more, I understand how they came to be and how they work.

That's why it bothers me so much when science deniers post their drivel to a worldwide audience thanks to a global network of machines that are doing all kinds of excessively clever things they are entirely ignorant of.

Obviously technologies like 'puters and smart devices are amazing but they are not like tactile where you can see/feel how it works...it's all black box tech and places the workings outside the ken of mere mortals like me.

Exactly: there is very little there to appreciate, unless you are a specialist, and what is there, doesn't do anything except funnel electrons around. A comparatively simple wind-up clock is infinitely more appealing. Add a pendulum, and I'm sold. Yes ... a tablet with a pendulum!

That's a transistor, your phone has millions of those just smaller. I played with these things as a child so to me it was a very tactile thing I could experiment with and try things out. Resistors, transistors and later logic gates and logic chips.... My dad has many fond stories of me figuring out binary logic using LED's and switches, etc.

So I guess at least to to me these are not black boxes. I know what's in there and I realise it's just what I did as a child but much smaller. I guess in a way it's a bit like molecular biology: It's more fully appreciated by a molecular biologist.

Besides, touching a live 220V wire with your bare hands is nothing if not a "tactile" experience.

I guess it comes as no surprise to you then that I don't find mechanical things all that alluring. I'll strip an engine if I must, but it's not something for which I have particular reverence.

For example, I stand in awe of the vernier scale as employed in measuring calipers. To me the concept of improving measurement twentyfold by simply sliding what amounts to two rulers relative to each other, is exceedingly cool. I appreciate the genius behind this because I almost, but not quite, understand why it works.

Rigil

For the benefit of those who are not familiar with the Vernier scale, here's an article explaining it. It's quite a clever invention.

I have one of those, it's one of the things me dad taught me to use as a kid. But now I have one that also has a convenient digital readout on it, and it wasn't even expensive!

But you know what you guys sound like, right? "These damn kids with their horseless carts! Back in my day a horse was your best companion, your friend, your confidant... These "cars" are just cold, unfeeling machines!"

Maybe modern computers don't give you the retro aesthetic you yearn back for ... but they do what a slide-rule does a billion times a second. They transport your sexts (and other less important communications like stock prices) to the other side of the globe in fractions of a second, possibly via space. They are not just the car to the horse, or the jet-airliner to the horse... they're like the lightspeed-capable spaceship to the horse... and you hold it in your hand.

Maybe that's the problem: the difference is so vast and so disruptive that it's just unfathomable, so people give up trying to even reconcile it with their world. It's "magic".

EDIT: As an aside, I recently discovered that my digital Vernier has SPI pins exposed on it's circuit board. In layman's terms: I can connect my vernier to my computer and read the current position out using my PC. Possibly track the position over time, etc... Even verniers aren't what they used to be.

Nobody can dispute the superiority of electronic technology. That does not preclude one from admiring inventions like the Vernier scale, the pendulum or the Six's thermometer. One may take it for granted or one might wonder: "Would I have thought of it?" and the answer is "probably not".

If it is indeed so that we show interest in and admire the technology that are basically comprehensible to us, then I venture that it also holds for some other things. Sport comes to mind. I've never really bothered to learn the rules of many popular South African ball games, and find watching it on TV very tedious (with the notable exception of women's beach volleyball).

Time travel.Forget about visiting the historical events, I would just like to go back and not make those stupid mistakes. But then I'll make other stupid mistakes I suppose. But this is (if humans could do it) something worthy of admiration.

Quote

Our Universe

Brian KoberleinShared publicly - Nov 1, 2015

Back To The Future Is Easy – It’s Back To The Past That’s Hard

According to Back To The Future Part II, October 21, 2015 was the day Doc and Marty arrive from the wonderful world of 1985. They’re greeted by a world of flying cars, hoverboards and self-lacing shoes.

As far as time travel is concerned, making the journey from 1985 to 2015 is easy. Many of us took the long road, traveling at the usual 1 second per second through time. But we know it’s possible to make the journey in less time. A central property of special relativity is time dilation, where an object moving at some speed relative to you will appear to experience time at a slower rate. We see this effect in particle accelerators, where unstable particles moving at high speed decay at a slower rate than ones at rest relative to us.

Using time dilation, you could in principle travel away from Earth at high speed and return 30 years later. If you traveled at speeds approaching light, then your journey might only take a month for you while decades pass on Earth. The power required for such a journey is far beyond the total energy production of Earth, but it’s possible within known laws of physics. Traveling forward in time is easy.

When folks talk of a time machine, however, they mean one that can travel backward in time. We want to be able to visit key moments in history, watch dinosaurs walk the Earth, or accidentally prevent our mother from dating our geek of a father. While it’s mostly just a fun plot device, time travel has been studied by physicists in great detail. Not necessarily with the goal of building such a machine, but rather to explore the theoretical possibilities of general relativity. What they’ve found is that backwards time travel is extremely difficult at the very least, but not necessarily impossible.

In physics a time machine is known as a closed timelike curve. Objects move through time and space, but can never travel through space faster than light. Any path through spacetime that obeys this rule is known as a timelike curve. If a timelike curve could somehow loop back on itself (if we could meet our younger self for example) it would be a closed timelike curve (CTC), hence a time machine.

It turns out that CTCs are possible within general relativity. In 1949 Kurt Gödel found a solution to Einstein’s equations with CTCs. It described a universe that rotated, and the rotation caused some timelines to loop back upon themselves. While Gödel’s universe is a mathematical solution to general relativity, it isn’t a physical one. The real universe doesn’t rotate the way Gödel’s model does. But Gödel showed that CTCs were at least theoretically possible within relativity, and so other solutions have been explored.

We now know that anything that allows travel faster than light could be used to create a time machine. If we had warp drive, then we could use time dilation and warp drive to create a CTC. The same is true for wormholes that allow us to create shortcuts across cosmic distances. As far as we know neither of these exist, and it seems the speed limit of light is also a rule against time travel.

But even if we assume time travel is somehow physically possible, there are also metaphysical problems with time travel. The most famous one is known as the grandfather paradox. It was first proposed by science fiction author Nathaniel Schachner in 1933, and is alluded to in the Back To The Future series. Shachner’s paradox had a time traveler journey to the past and kill his grandfather before he married and had children. Since this prevented the time traveler from being born, he couldn’t have killed his grandfather, hence the paradox. In Back To The Future, Marty accidentally prevents his parents from going to the school dance, thus putting his very existence in danger.

Interestingly, the grandfather paradox is easily resolved in general relativity through what is known as the Novikov self-consistency principle. If we assume that (somehow) CTCs are possible, then the Novikov principle requires that such time loops be self consistent. So you could travel back in time in an attempt to assassinate your grandfather, but only end up wounding him. He’s rushed to the hospital, where the attending doctor is none other than your grandmother. Your time-trip caused them to meet, and hence you were born, which is perfectly consistent. According to the Novikov principle, it would be physically impossible to create a paradox. This self consistent approach was used in that other 80’s time travel movie, Bill & Ted’s Excellent Adventure.

Back To The Future uses a different take on time travel, specifically that traveling back in time would spawn a new timeline. Even though Marty reunites his parents by the end of the first film, there are small differences when he returns to 1985. As the trilogy progresses a wide range of timelines are formed (up to 21 depending on how you count them). This draws upon what is known as the many worlds model.

In quantum theory, the measurement of a quantum object leads to an outcome that is probabilistic. Rather than a deterministic cause and effect, as seen in Newtonian physics, quantum theory can only give us the likelihood of a certain result. In an effort to bring determinism to quantum measurements, Hugh Everett proposed a “relative state” interpretation of quantum theory in 1957. In this interpretation, all outcomes of a quantum measurement occur, but the act of measurement causes the outcomes to separate from each other. Basically, a quantum measurement causes the universe to split into separate “universes,” each with a different outcome. While Everett’s model isn’t that simple, the idea that events or choices can split the universe has become a popular trope in science fiction. The idea of time traveling between parallel worlds isn’t plagued with the paradoxes of single-universe time travel, but it relies upon a loose interpretation of an unproven model.

Because of the challenges and paradoxes of backwards time travel, most physicists don’t think time travel is possible. All the metaphysical problems go away if a time machine is simply unphysical, and in physics the simplest answer is usually the right one. So perhaps we should focus on things that, though highly unlikely, are in principle physically possible. Such as the Cubs winning the World Series.

An entertaining and informative write-up but Koberlein doesn’t mention that it’s also theoretically possible to create CTCs around an enormously dense and fast-spinning mass, e.g. neutron stars or small black holes. This possibility indicates that backward time-travel is encumbered by vastly greater energy requirements.